Areas of the sanctuary will be
designated to represent various concepts, such as saints, virtues and sins, and
secular concepts such as regions of Spain, presumably with decoration to match.

columns

The building works are expected to be
completed around 2026, the 100th anniversary of Gaudi's death, although the
likelihood of meeting this date is disputed. Computer modelling has been used
for the detailed design of the intricate structure of supporting columns inside
the basilica. See also catenary. CAD/CAM technology has been used to speed up
the construction of the building; initially, the construction work was expected
to last for several hundred years, based on building techniques available in the
early 1900s. The construction work calls for many pieces of stone to be machined
to unique shapes, each being subtly different from the next, and these pieces
are now being machined accurately off-site, reducing the overall construction
time.